Spate of cloudburst like events cause damage on Char Dham project route
This year’s Char Dham yatra, a pilgrimmage to the four holy shrines in the state of Uttarakhand, may have been scaled down to a symbolic event on account of the pandemic, but recent meteorological events highlight the dangers facing the ongoing project to widen the road connecting the four shrines, the Char Dham highway.
An analysis by India Meteorological Department concludes that a cloudburst like event occurred in the upper reaches of Devprayag in Tehri Garhwal district on Tuesday evening leading to a sudden rise in water flow in a seasonal rivulet, Gadera. Heavy flow of water in the rivulet damaged buildings, other infrastructure and took debris up to Alaknanda.
Environmentalists opposed to the Char Dham project, which envisages the widening of the Char Dham highway -- the Supreme Court will hear a case related to this on May 13 -- fear that if a cloudburst were to occur in the midst of the roadwork, it could prove disastrous for the workers, and damage the hills even more.
A bench comprising Justice Vineet Saran and Justice Dinesh Maheshwari posted the matter for hearing while observing that issue of widening of roads leading to the China border is of national importance.
“Our data indicates about 25 mm rain in an hour was recorded at Devprayag. If you go by the exact definition of cloudburst, it’s at least 10 cm rain received in an hour. But we have evidence that even 3 to 5 cm rain in an hour can trigger severe mudslides and landslides because soil is very loose in this region. We suspect that is what has happened in Devprayag,” said M Mohapatra, director general, IMD.
According to IMD, if 10 cm rainfall is received at a station in one hour, the rain event is termed as cloud burst. It is very difficult to predict the cloud bursts due to its very small scale in space and time.
Such meteorological events have become common in Uttarakhand.
Another internal IMD report based on local media reports said a cloud burst type event was reported at Tehri, Uttarkashi, Rudraprayag and Chamoli districts in early hours of May 3. This damaged several roads and bridges. Some shops at Binsar in Chamoli district were buried under debris. On the afternoon of May 5, “cloudburst like impact” and hailstorm were reported from Chaukhutia, Almora. Central Water Commission (CWC) data showed water level at Naula in Ramganga river rose by 78 cm due to heavy rain.
“The rain recorded on Tuesday is not very heavy. They are mostly in the range of 25 to 35 mm. During the pre-monsoon season the soil is very loose and there are high chances of landslides even when there is not much rain. We are trying to understand why such heavy damage took place. There are two radars also in Uttarakhand and we are getting data from there too,” said M Rajeevan, secretary, ministry of earth sciences.
“There have been several incidents of cloud bursts and heavy rain in April and May which have caused extensive damage on the Char Dham yatra route. Any hill cutting for road construction is not only not advisable but also not possible in the midst of such natural hazards,” said Mallika Bhanot of Ganga Ahvaan, a Uttarakhand based NGO.
“This is the sixth heavy rainfall incident in the pre-monsoon season that has caused damage to roads and property in Uttarakhand. If Char Dham road widening work continues through pre-monsoon and monsoon season it will aggravate risks of landslides and other disasters,” said D P Dobhal, a former glaciologist at Dehradun-based Wadia Institute of Himalayan Geology.
IMD’s analysis also cites research by IMD scientists based on long-term data of rainfall, landslide and flash floods that rainfall of 3-5 cm per hour in the steep slope mountainous regions of Himalayas can cause flash floods, landslides, debri flows, flash floods with huge damages to properties and human losses irrespective of rainfall amount.
More rain is expected over the Western Himalayan region. A western disturbance as a trough (low pressure area) is impacting the region. A cyclonic circulation is lying over Punjab and neighbourhood and an east-west trough is running from this cyclonic circulation to Sub Himalayan West Bengal and Sikkim at lower levels.
In September , the Supreme Court directed the width of the Char Dham road be 5.5 metre based on a minority report of a 26-member High Powered Committee (HPC). This width was fixed as per a 2018 notification issued by the Ministry of Road, Transport and Highways (MoRTH). Later, the ministry amended its notification and filed an application in the top court against its September 8, 2020 order. The Ministry of Defence too filed a separate application in December last year supporting MoRTH. It requested the court to allow the road width to be increased to 7 metres.